Comparing two arrays of objects, and exclude the elements who match values into new array in JS

javascript arrays underscore.js javascript-objects lodash

well, this using lodash or vanilla javascript it depends on the situation.

but for just return the array that contains the differences can be achieved by the following, offcourse it was taken from @1983

var result = result1.filter(function (o1) {    return !result2.some(function (o2) {        return o1.id === o2.id; // return the ones with equal id   });});// if you want to be more clever...let result = result1.filter(o1 => !result2.some(o2 => o1.id === o2.id));

javascript arrays underscore.js javascript-objects lodash

Just using the Array iteration methods built into JS is fine for this:

var result1 = [    {id:1, name:'Sandra', type:'user', username:'sandra'},    {id:2, name:'John', type:'admin', username:'johnny2'},    {id:3, name:'Peter', type:'user', username:'pete'},    {id:4, name:'Bobby', type:'user', username:'be_bob'}];var result2 = [    {id:2, name:'John', email:'johnny@example.com'},    {id:4, name:'Bobby', email:'bobby@example.com'}];var props = ['id', 'name'];var result = result1.filter(function(o1){    // filter out (!) items in result2    return !result2.some(function(o2){        return o1.id === o2.id;          // assumes unique id    });}).map(function(o){    // use reduce to make objects with only the required properties    // and map to apply this to the filtered array as a whole    return props.reduce(function(newo, name){        newo[name] = o[name];        return newo;    }, {});});document.body.innerHTML = '<pre>' + JSON.stringify(result, null, 4) +        '</pre>';

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